NHTSA Wants Hybrids, EVs to Be Noisier

In an effort to make streets safer for pedestrians, the National Highway Traffic Administration (NHTSA) has proposed a rule that could require engineers to add more sound to hybrids and electric vehicles (EVs).

The proposed rule, a follow-on to the Pedestrian Safety Enhancement Act of 2010, would likely require that automakers add external speakers to hybrids and EVs. NHTSA estimates that such speaker systems would add about $30 to the manufacturing cost of the cars, but could prevent about 2,800 injuries over the life of each vehicle model year.

"Our proposal would allow manufacturers the flexibility to design different sounds for different makes and models while still providing an opportunity for pedestrians, bicyclists, and the visually impaired to detect and recognize a vehicle and make a decision about whether it's safe to cross the street," NHTSA administrator David Strickland said in a press release.

The mandate is the result of numerous studies over the past five years that have shown that the incidence of pedestrian crashes is higher among hybrids and electric cars. A 2009 study from NHTSA conducted on 8,287 hybrids and 559,703 conventional vehicles showed that hybrids were "two times more likely to be involved in a pedestrian crash." Similarly, a study done in Japan at the request of the Japanese Federation of the Blind revealed that more than half the blind respondents were "terrified" of hybrids.

NHTSA's mandate would provide leeway for automakers as to the kinds of sounds, but it does call for them to be detectable under a wide range of street noises and ambient background sounds.

Some hybrids and EVs already incorporate mechanisms for additional sound. Toyota's Prius and RAV EV vehicles, for example, employ a Vehicle Proximity Notification System (VPNS), which is located under the hood and emits sounds at speeds under 15mph. VPNS includes low- and high-frequency sounds that mimic Toyota's internal combustion engines. "It's a retrofitted little speaker behind the front grille," Jana Hartline of Toyota told Design News. "It's not anything that can be heard inside the car, but it is distinctive."

NHTSA said it will give the public 60 days to comment on the proposed mandate. Automakers are expected to work with the agency on the development of a standard. "We've studied it on our own and we will continue to work with NHTSA on it," Hartline said.

Car manufacturers are considering making rear video cameras with obstacle alarms standard on future models. With large LCD touch screens becoming the dashboard norm the display device will already be in place and paid for. Some vehicles already have radar devices that will signal the driver and/or apply the brakes upon detection of an imminent collision.

As the baby boomer generation greatly expands the elderly driver population, the need for these additional safety devices and even self driving vehicles will become more evident.

I agree that quiet vehicles, in fact all vehicles, should have rear mounted backup alarms. But that may not reduce the number of children run over by vehicles.

I commute by bicycle most of the year on roads (no bike lanes here), and from my experience, as Charles has pointed out, the engine noise is not audible on most new cars when they are going at 40 or 50mph. However, I do hear the cars approaching behind me, or rather the tire noise and wind noise the cars are making. Adding extra cost to the cars and extra noise to our cities based on "seems like a good idea" but without actuall data to support the claims, is absurd.

The argument that noisy cars will save lives is just as absurd as motorcyclists that say their loud pipes save lives. I used to have a sport bike (Katana 600) with a very loud pipe and I still had cars that would try to run me off the road because they did not see me or hear me when I was right next to them. Riding that bike or my later quieter bike, there was absolutely no difference in how people didn't pay attention. Making something louder will not substitute for peoples lack of attention.

Idiotic safety regulations predate the always on headlight by a few decades! You might be too young to remember the dual volume level car horn. But indeed there was an ordinance passed in some States that required vehicles to have a horn with two volume settings.

Okay, so this could make some sense to reduce noise pollution, if only it wasn't bass ackwards.

You see, the motor vehicle rule was thus. In the city you had to use the low setting for your car horn. In the country you were supposed to use the loud setting!!!!???? The concept was to reduce noise pollution levels in our cities.

You do realize that with the city's much higher ambient noise floor due to all manners of noise generation, density of people, elevated rapid transit trains, construction noise, you really need to keep the vehicle horn loud enough to be heard in a sufficent intensity to shout out its intended warning.

In the countryside a much softer horn would suffice and would be in better keeping with the character of the location.

And yes there were more avoidable fender benders in town due to inaudible car horns.

Having been almost backed over five times while walking in a somewhat noisy parking structure, this is a welcome idea.

The Prius, which is the car that I usually have problems with, is absolutely silent in reverse. Its backup lights are so focused that you don't see them unless directly behind the vehicle. Flashing side lights might be a good idea here. There is a backup alarm on the Prius but for unknown reasons, it is in the passenger compartment and not outside! If they do put an auditory warning device (the horn?) on EVs, it should have volume controlled in proportion to ambient noise.

My beef is only with backup where the driver may not have the best visibility. In forward, it is the mutual responsibility of the driver to yield to pedestrians and the pedestrian to be aware (ok, maybe that's a reach) of their environment and act accordingly.

btw- loved the comment about baseball cards in the spokes. Took me back to 1955 <smile>.

I'm ambivalent too. Why do we insist upon increasing the noise of civilization? It's one reason I now live in the country although I was born and raised in a big city.

I suppose one could design noisy tires and wheels for low noise vehicles which would provide a retrofit for quiet hybrids or all electric vehicles rather than adding a speaker and electronics to make additional noise. Will this add yet another vehicle inspection test to check for a properly working anti-stealth noise box?

I can see the lawsuits from the estates of folks run over by vehicles with faulty noise generators! And I can see high paid lawyers winning huge awards from the vehicle operator, owner or manufacturer when the deceased should have taken ownership of blame for not looking both ways.

Might it be better to equip all new vehicles with some sort of RF beacon transponder that could alert deaf, blind or non-observant folks of the proximity of a moving vehicle heading towards them? The pedestrian would wear a small device, maybe incorporated into a wrist watch or cell phone handset that would warn them of approaching moving hazards. And the vehicle driver could also be warned that a deaf or blind pedestrian was lurking between parked vehicles ready to lurch out into the lane of traffic.

Heck, you could also provide dog collars to help reduce the death of pets from being run over by vehicles. And in rural areas the State fish and game departments could put RF collars on the deer herd. Well maybe not, as I'm sure a clever hunter/engineer might use same during hunting season to get the upper hand on bringing home the venison.

If you look at mail order catalogs from outdoors marketers you can find whistles designed to be affixed to motor vehicles with the intention of warning wildlife of your presence. They don't work!

Imagine this scenario. On a street corner an offical from local government department of transprotation is holding a sound pressure meter. But instead of looking for vehicles that are louder than permitted, i.e. a bypassed muffler, they are looking to pull over vehicles that are too quiet!

Hi. I was ready to call the NHTSA some choice names but I see my fellow EEs have taken care of that. Ok I can't help it: this is stupid!

First was the equally idiotic daylight running lights because we were already too distracted to notice the oncoming car. Now, after improving our cars to make them as quiet as possible, we need to add the noise back in.

Really? What's next, the horn will be always on as soon as you start the car? Every car must have a disco ball install on top to project flashing beams out and be noticed? Large trees will be fitted with 150dB sirens to warn us they're there! Noise cancelling headsets will be reversed to amplify every minute sound around us. People will be made to wear whoopee cushions under their shoes so they make noise with every step... god forbid someone might bump into another while walking.

A Prius made contact with me in Paris, nobody hurt... but it could have been far worse. This is one of those things that I do not feel ambivalent about. 30 bucks of product cost is a BARGAIN if you want to look at automotive mandates and compare... airbags, seat belts, energy absorbing bumpers, bolster-absorption interior design, recyclability, speed-sensitive features, ABS [I liked 4-wheel non-ABS Disc brakes better]. This one's cheap and effective. I hate regulations as much as the next guy but I don't want to run over blind people either.

For years the goal was to make cars quieter. Environmental noise pollution is real and persistent. And now the NHTSA want to make our cars noisy?! Completely ridiculous. If you care about quiet, voice your opposition to this rule at:

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